GNU nano

http://www.nano-editor.org/
Nano is a small and user-friendly text editor. It has an interactive search-and-replace function with regular-expression support, a spell-checker function, a goto-line command, variable tab width, auto-indent, syntax coloring, undo/redo, slang curses-wrapper and GNU autoconf support, and toggles for command-line flags that can be used from within the editor.

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